A budget generally refers to a list of all planned expenses and revenues (or incomes) for a particular time period (i.e., budget cycle). The budget cycle is typically a period in the future, for example a month, a quarter, or a year. A budget typically helps an individual or a business determine when income will be sufficient to cover expenses and help forecast when a large expenditure (e.g., a purchase of products, services, etc.) can be made.
Price erosion is a result of market competition, technology maturity, etc. that causes the price of a product, service, or other items to decrease in time. As a result, a purchase planned in the future can often be made at a lower price than the current price when the budget is initially created.
Electronic Commerce, commonly known as e-commerce, involves buying and selling of products, services, or other items over electronic systems such as the Internet and other computer networks. Vendors that participate in the e-commerce are referred to as e-commerce merchants.